Despite the fast acceleration of wind energy implementation, wind turbine noise is still one of the major obstacles for the widespread use of wind energy in Europe. For modern large turbines, aerodynamic (in particular trailing edge) noise is considered to be the dominant noise source. The principal objective of the present project is to develop airfoils and possible other concepts, by which the aerodynamic noise of full-scale wind turbine blades can be reduced considerably (say 3-6 dB), without a reduction in power performance. The airfoils will be designed using a new combined acoustic-aerodynamic design methodology. This methodology is based on the method from the previous EU-project DATA to design acoustic blades for a wind tunnel model rotor. In the present project the method will be extended for the full-scale situation. The performance of the turbines will be validated using a new measurement technique which can localise and quantify noise sources on a rotating blade.